The marquee CSS properties are a replacement for the non-standard HTML <marquee> tag.
The overflow-x property also has to be set before the marquee will take effect.

Try it:

A stationary object remains stationary if the sum of the forces acting upon it - resultant force - is zero. A moving object with a zero resultant force keeps moving at the same speed and in the same direction.

(CSS 3) Browser Support: None. Use the equivalent -webkit-marquee-repetition for Safari and Chrome.

“Be daring, be different, be impractical, be anything that will assert integrity of purpose and imaginative vision against the play-it-safers, the creatures of the commonplace, the slaves of the ordinary” ~ Cecil Beaton